Process for dyeing mixtures of cellulosic and polyester fibers with reactive and disperse dyestuffs



United States Patent US. Cl. 8-21 8 Claims ABSTRACT OF THE DISCLOSURE A process for dyeing mixtures of cellulosic fibers and high molecular weight linear polyester fibers which comprises using an aqueous dyebath which contains both reactive and disperse dyestuffs, an alkaline compound to give the bath an initial alkaline pH and an acid donator which reacts with water, when heated, to split off a hydrogen halide and thereby reduce the pH of the bath during the. dyeing process. The reactive and disperse dyestuffs used are conventional. The alkaline compound may be, for example, an alkali metal carbonate, bicarbonate, triphosphate or hydroxide. The acid donator may be any of a wide variety of halogenated compounds, typically salts, amides or anilides of monoand di-halogenated acetic and propionic acids, e.g., chloracetamide. The bath is heated to a temperature of, e.g., 125 C. to cause the acid donator to split off the hydrogen halide and reduce the pH of the bath. Uniform dyeing of both types of fibers is achieved.

It is known that reactive dyestuffs can be fixed in an alkaline medium. For example a medium prepared using alkali metal hydroxides or alkali metal salts of weak organic acids, on cellulosic fibrous materials. In practice, this fixation in the dyeing or printing with reactive dyestuffs is carried out with the, use of an excess of alkaline substances or of substances which have an alkaline action. When alkali metal hydroxides or alkali metal carbonates are used, the pH-value remains constant during the Whole fixing process. Whenalkali metal'bicarbonates are used,

the pH-value strongly rises shortly after the beginning of erally carried out at a neutral to weakly acidic pH-value,

whereas an alkaline pH-value is required for the fixing of reactive dyestuffs. Furthermore, in the case of reactive dyestuffs, a prolonged treatment with alkaline substances at elevated temperatures strongly reduces the yield of dyestuff being fixed on the fibers, which reaction is due to a splitting of the dyestuff-fiber linkage.

1 Furthermore, with the alkaline agents commonly used in dyeing, for example, alkali metal bicarbonates, alkali metal carbonates or alkali metal hydroxides, it is not possible to fix reactive dyestuffs on cellulose according to the exhaust process at those elevated temperatures of above about 95 C. which are required for the dyeing of the polyester fiber portion with disperse dyestuffs. Finally, most. of the disperse dyestuffs are chemically modified by a prolonged action of alkaline substances at elevated tem- Patented Dec. 8, 1970 peratures, which results in a deterioration of the properties of fastness and of the shade.

Now, We have found that the above-described disadvantages can be avoided and that mixtures of cellulosic fibers with fibrous materials made of linear polyesters can be dyed simultaneously with reactive and disperse dyestuffs according to the exhaust method at temperatures of above C., by using dyebaths which contain, in addition to the above-mentioned dyestuffs, alkaline substances and halogenated organic compounds which act as acid donators by reacting with water, preferably at elevated temperature, to split off hydrogen halide and, if desired or required, the carriers commonly used in the dyeing of poly ester fibers.

The addition of halogenated organic compounds, which act as acid donators, to the dyebaths according to the present invention results in a reduction of the pH-value during the fixing process. This not only permits the use of reactive dyestuffs in the exhaust process at temperatures of above 100 C., but also considerably reduces the risk of a breaking of the fiber-dyestuff linkage. Furthermore, in the process of the present invention, the disperse dyestuffs do not undergo chemical modification.

The quantity of halogenated organic compounds which act as acid donators and which are to be added to dyebaths depends above all on the quantity of alkaline substances contained in the baths. If this content of alkaline substances is in the usual range, the halogenated organic compounds are generally added in quantities ranging from about 0.4 to 40 g./l. of dyebath. The quantity of halogenated organic compounds is so chosen that, after splitting off of hydrogen halide, a pH-value of below about 8.0 is obtained.

As halogeanted organic compounds, which act as acid donators in the process of the present invention, there may be used especially aliphatic, cycloaliphatic or heterocyclic compounds containing one or more halogen atoms and which correspond to the following general formula X Ilia H s- )1. Y R2 n In the above formula X represents chlorine, bromine, iodine or hydroxyl,

Y represents hydrogen, hydroxyl, alkyl, phenyl, chlorine,

bromine or iodine,

Z represents hydrogen, alkyl, phenyl or the radical n represents 0 or an integer from 15,

R represents hydrogen, hydroxyl, chlorine, bromine or iodine, or alkyl or phenyl radicals which can contain hydrosolubilising groups such, for example, as COOH, -SO H or --OH, at least one of X, Y and R being halogen,

R represents hydrogen or alkyl or phenyl radicals WhlCh may contain hydrosolubilising groups such, for example as COOH, --PO H SO H or OH,

R represents hydrogen, --OH, CHO, COOH,

SO H, --CONH --CONH-alkyl, CN, CON- 'SO2NH2, SO NH-alkyl,

-CH-;QH2

or a radical of the formula 3 wherein A represents O-, CO-, SO-, SO CONH--, SO NH, CON(alkyl), CON- (phenyl)-, SO N(alkyl) or -SO N(phenyl); the alkyl and phenyl radicals may contain hydrosolubilising groups. Furthermore, R may represent a radical A which is bound with C over the group which in the general formula stands instead of Z, thus forming a ring system.

As alkyl radicals in the above general formula, there are to be understood preferably low molecular weight alkyl radicals containing about 1-6 carbon atoms. The phenylradicals may carry additional substituents, for example, low molecular weight alkyl radicals.

As suitable halogenated organic compounds which in an aqueous medium, preferably at elevated temperatures, react with water under splitting off of hydrogen halide, there may be mentioned, by way of example:

chloroacetic acid 3-chloro-propinoic acid phenyl-chloroacetic acid 3-chloro-propinonic acid nitrile ethylene-chlorhydrin 1,3-dichloro-propanol-(2) 1-chloro-propanol-(2) 3-chloro-propylene oxide 2-chloro-ethane-sulfonic acid l-chloro-propanol-(2)-sulfonic acid -(3) 3-chloro-propane-diol- 1,2) l-chloro-caprolactam 2-trich1oromethyl-propanol- (2) 3-chloro-propionaldehyde dichloroacetic acid and the alkali metal salts, especially the sodium or potassium salts, amides or anilides of the aforementioned acids.

According to the process of the present invention, the halogenated organic compounds which act as acid donators are added to the dyebaths in such quantities that after the splitting off of hydrogen halide a pH-value of below 8.0, suitably below 7.5 and preferably in the range of between 4 and 6 is obtained. The quantity of halogenated organic compounds to be added depends thus on the quantity of alkaline substances used and therewith indirectly on the quantity of reactive dyestuffs used. Generally, the quantity of halogenated organic compounds to be added to the dyebath will be in the range of about 0.1 to parts by weight, especially 1-5 parts by Weight per one part by weight of reactive dyestuff, provided that the pH-value of the bath is in the range which is usual in the dyeing with reactive dyestuffs.

As alkaline substances which are required for the fixation of the reactive dyestuffs, there may be used organic compounds having an alkaline action or, advantageously, inorganic alkaline susbtances such as sodium carbonate, sodium bicarbonate, sodium triphosphate, sodium hydroxide, the corresponding potassium compounds or mixtures of these alkaline substances. The alkaline substances are used in such quantities that the dyebaths have a pH- value of above 8.0, preferably in the range of 9-12. Generally, the alkaline substances are added to the dyebaths in quantities of about 0.1-10 g./ 1.

As disperse dyestuffs, there may be used the dyestuffs generally known as suitable for the dyeing of fibrous materials of linear polyesters, for example the dyestuffs of the azo or anthraquinone series.

As reactive dyestuffs, there may be used organic dyestuffs which contain at least one group capable of reacting with the cellulose fiber or a precursor to such a group or also a substituent which is capable of reacting with the cellulose fiber. As parent component of the organic dyestuffs, there are especially suitable those of the series of the anthraquinone, azo and phthalocyanine dyestuffs; the azo and phthalocyanine dyestuffs maybe metalfree or metallised. As reactive groups or as precursors which form such reactive groups in an alkaline medium, there may be mentioned, for example, the epoxy group, ethylene imide groups, the vinyl radical in a vinyl-sulfone group or in the acrylic acid group, furthermore the B-sulfatoethyl-sulfonyl group. As reactive substituents, there enter into consideration substituents which can easily be split off and leave behind an electrophilic radical; as examples of such substituents, there may be mentioned halogen atoms in the following ring systems: quinoxaline, triazine, pyrimidine, phthalazine and pyridazone.

The carriers which may be used simultaneously may be those commonly used in the dyeing of polyester fibers, for example o-phenyl-phenol, p-phenyl-phenol, benzoic acid alkyl esters, salicylic acid alkyl esters and similar compounds. 'Other suitable carriers are, for example, those described in the papers published in Melliand Textilberichte (1961), page 1275, and (1960), page '198, as well as in Textil-Praxis (1957) pages 383-384, and in the ICI-Technical Report The 'Dyeing of Terylene, part I, dated Dec. 11, 1947.

The following examples illustrate the invention but they are not intended to limit it thereto:

EXAMPLE 1 5 grams of a mixed yarn of 70 parts of polyester fibers and 30 parts of staple fibers were dyed for 1 /2 hours, at a goods-to-liquor ratio of 1:20, in a closed dyeing apparatus, at C., in a dyebath containing 1%, referred to the weight of the goods, of the disperse dyestuff of the formula NH: O OH I /II\ I I OH O NH:

having the form and composition usual in commerce, and 5% of the reactive dyestuff of the formula if w 0 SOaNa o H 0 NH- having the form and composition usual in commerce, and

1 gram/ liter of sodium carbonate, 4 grams/ liter of chloroacetamide, and 12.5 grams/ liter of sodium sulfate.

After dyeing, the goods were rinsed hot and soaped with 1 gram/liter of an anion-active or non-ionic detergent, rinsed again and dried. A uniform brilliant blue dyeing was obtained.

EXAMPLE 2 5 grams of a mixed fabric of 67 parts of polyester fibers and 33 parts of cotton were dyed for 1% hours 5 at a goods-to-liquor ratio of 1:40, in a boiling dyebath containing, referred to the weight of the goods:

1.5% of the disperse dyestuff of the formula having the form and composition usual in commerce, 1.5% of the reactive dyestuff of the formula having the form and composition usual in commerce, and

1 gram/ liter of sodium carbonate,

4 grams/ liter of chloroacetamide,

25 grams/ liter of a carrieron the basis of methylnaphthalene in the form usual in commerce, and

12.5 grams/liter of sodium sulfate.

After dyeing, the goods were rinsed, soaped and dried as usual. Both types of fibers of the fabric were dyed a brilliant red shade.

I claim:

1. In a process for dyeing mixtures of cellulosic and high molecular weight linear polyester fibers according to an exhaust method in a single bath containing both reactive and disperse dyestufls and an inorganic alkaline substance to render said bath alkaline, the improvement which comprises incorporating in said bath an acid donator which is a halogenated organic compound that at an elevated temperature reacts with water to split off a hydrogen halide, and heating said bath to a temperature above 100' C. to cause said acid donator to produce 45 potassium salts and unsubstituted amides of the aforementioned acids.

2. A process as claimed in claim 1, wherein the halogenated organic compound is added in a quantity such that during the dyeing process the pH-value of the bath 0 5. A process as claimed in claim 4, wherein the alkaline substance is added in a quantity that the pH-value of the bath is initially within the range from 9 to 12.

6. A process as claimed in claim 1, wherein the alkaline substance used in sodium carbonate, sodium bicarbonate, sodium triphosphate, sodium hydroxide, the corresponding potassium salts or mixtures of these alkaline substances.

7. A process according to claim 1 in which the acid donator is chloracetamide.

8. A process as claimed in claim 1 and wherein the bath contains a carrier selected from o-phenyl-phenol, p-phenyl-phenol, a benzoic acid alkyl ester of a salicyclic acid alkyl ester.

References Cited UNITED STATES PATENTS 3,288,551 11/1966 Raff 8-92X 3,122,530 2/1964 Price et al. 81.(23)

3,150,916 9/1964 Karacsonyi et al. 839X FOREIGN PATENTS 640,910 4/1964 Belgium 81(:23)

50 DONALD LEVY, Primary Examiner US. Cl. X.R. 

